Using a small, sharp knife, cut a slit down the side of each chicken breast to form a deep pocket. Mix together the remaining ingredients in a bowl, then season well. Divide the mixture evenly between the 4 chicken pockets.
Drizzle with a little oil, then transfer to a nonstick baking sheet. Place in a preheated oven, 180°C (350°F), Gas Mark 4, for 18–20 minutes or until the chicken is cooked through.
Serve with steamed jasmine rice and Chinese greens.